To use a key, the player selects the key in their backpack and clicks the 'Use with...' button before selecting the crate they wish to be opened. The key can be used with any regular series crate in the player's backpack, where it is consumed, along with the crate, in the process.

During some special events, specialized keys are made available. These keys can be used with specifically associated series of crates, which regular keys cannot open. Remaining special keys, at the end of promotions, are transformed into regular keys.

Keys cannot be found from random drops and cannot be crafted. Upon purchase, they are untradable for 7 days, provided the user's first Steam purchase was more than 30 days ago. Otherwise, a 3-day waiting period is imposed. Uncrated items will inherit the trade restrictions of the keys used to open the crate(s).

Stocking Stuffer Key

Stocking Stuffer Key

Level 5 ToolSomeone left this key in your best pair of fightin' socks. It looks like it will open any festive or normal crate.

This is a limited use item. Uses: 1

( Not Tradable )

The Stocking Stuffer Key was a key given by Miss Pauling to the Team Fortress community in honor of Australian Christmas. One key was given out to each active player and it could open both the limited time Festive Winter Crate and regular Mann Co. Supply Crates. Unlike the Festive Winter Crate Key, these keys were untradable and did not revert to a regular Mann Co. Supply Crate Key.

Refreshing Summer Cooler Key

Refreshing Summer Cooler Key

Level 5 ToolUsed to open unusually refreshing locked summer coolers. After 7/11/2011 this will turn into a normal key.

This is a limited use item. Uses: 1

The Refreshing Summer Cooler Key was a single-use tool item that was released during the Summer Camp Sale update. Like regular keys, they could be purchased in the Mann Co. Store and was used to open a Refreshing Summer Cooler. They can no longer be obtained and any remaining Cooler Keys have turned into normal keys after the July 12, 2011 item schema update.

Naughty Winter Crate Key

Naughty Winter Crate Key

Level 5 ToolUsed to open unusually Naughty locked winter crates.This key will not open Nice crates.

Scorched Key

Scorched Key

Level 5 ToolUsed to open Scorched Crates.After 7/11/2012 this will turn into a normal key.

This is a limited use item. Uses: 1

The Scorched Key was a single-use tool item that was released during the Pyromania update. Like regular keys, they could have been purchased in the Mann Co. Store. The Scorched Key could be used to open a Scorched Crate. Scorched Keys turned into regular keys after the July 11, 2012 Patch.

Fall Key

Fall Key

Level 5 ToolUsed to open Fall Crates.After 9/20/2012 this will turn into a normal key.

Eerie Key

Level 5 ToolUsed to open Eerie Crates. Eerie Crates contain Halloween-themed items that are only visible during the Halloween event and full moons.

After 11/08/2012 this will turn into a normal key.

This is a limited use item. Uses: 1

The Eerie Key was a single-use tool item that was released during the October 26, 2012 Patch. Like regular keys, they could have been purchased in the Mann Co. Store. The Eerie Key could be used to open an Eerie Crate. Eerie Keys turned into regular keys after November 8th, 2012.

Naughty Winter Crate Key 2012

Naughty Winter Crate Key 2012

Level 5 ToolUsed to open Naughty Winter Crate 2012.This key will not open Nice crates.

After 1/3/2013 this will turn into a normal key.

This is a limited use item. Uses: 1

The Naughty Winter Crate Key 2012 was a single-use tool item which was released during the Mecha Update. Like regular keys, they could have been purchased in the Mann Co. Store and could be used to open a Naughty Winter Crate 2012. Naughty Winter Crate Keys 2012 turned into regular keys after January 03, 2013.

Nice Winter Crate Key 2012

Nice Winter Crate Key 2012

Level 5 ToolUsed to open Nice Winter Crate 2012.This key will not open Naughty crates.

After 1/3/2013 this will turn into a normal key.

This is a limited use item. Uses: 1

The Nice Winter Crate Key 2012 was a single-use tool item which was released during the Mecha Update. Like regular keys, they could have been purchased in the Mann Co. Store and could be used to open a Nice Winter Crate 2012. Nice Winter Crate Keys 2012 turned into regular keys after January 03, 2013.

Summer Appetizer Key

Summer Appetizer Key

Level 5 ToolUsed to open locked Summer Appetizer Crates

This is a limited use item. Uses: 1

The Summer Appetizer Key is a single-use tool item which was released in the July 2, 2013 Patch. Like regular keys, they can be purchased in the Mann Co. Store and can be used to open one Summer Appetizer Crate. A Summer Appetizer Crate will contain one item from the first set of Gold Star approved Community items. These items came from the Steam Workshop through the in-game Workshop item import tool.

Spooky Key

Spooky Key

Level 5 ToolUsed to open Spooky Crates.After 11/11/2013 this will turn into a normal key.

This is a limited use item. Uses: 1

The Spooky Key was a single-use tool item which was released in the October 29, 2013 Patch. Like regular keys, they could have been purchased in the Mann Co. Store. They could be used to open one Spooky Crate. Spooky Keys turned into regular keys on November 12, 2013.

Naughty Winter Crate Key 2013

Naughty Winter Crate Key 2013

Level 5 ToolUsed to open Naughty Winter Crate 2013. This key will not open Nice crates.After 1/6/2014 this will turn into a normal key.

This is a limited use item. Uses: 1

The Naughty Winter Crate Key 2013 was a single-use tool item which was released in the December 20, 2013 Patch. Like regular keys, they could have been purchased in the Mann Co. Store. They could have been used to open one Naughty Winter Crate 2013. Naughty Winter Crate Keys 2013 turned into regular keys on January 6, 2014.

Nice Winter Crate Key 2013

Nice Winter Crate Key 2013

Level 5 ToolUsed to open Nice Winter Crate 2013. This key will not open Naughty crates.After 1/6/2014 this will turn into a normal key.

This is a limited use item. Uses: 1

The Nice Winter Crate Key 2013 was a single-use tool item which was released in the December 20, 2013 Patch. Like regular keys, they could have been purchased in the Mann Co. Store. They could have been used to open one Nice Winter Crate 2013. Nice Winter Crate Keys 2013 turned into regular keys on January 6, 2014.

Limited Late Summer Crate Key

Level 5 ToolUsed to open Limited Late Summer Crates. Late Summer Crates contain limited items that only come from it.

After 10/13/2014 this will turn into a normal key.

This is a limited use item. Uses: 1

The Limited Late Summer Crate Key was a single-use tool item which was released in the September 25, 2014 Patch. Like regular keys, they could have been purchased in the Mann Co. Store. They could have been used to open one Limited Late Summer Crate. Limited Late Summer Crate Keys turned into regular keys on October 13, 2014.

End of the Line Key

End of the Line Key

Level 14 ToolUsed to unlock an End of the Line Community Crate.Items found from an EOTL Community Crate before January 5th, 2015, will receive a commemorative early supporter tag.

Bugs

The quality of the backpack icon for the End of the Line Key is affected depending on the Texture Quality of the game, which isn't a normal behavior, as other backpack icons for other items aren't affected depending on the Texture Quality that the player set.

Trivia

The backpack image for the key is a screenshot of a key model. The model was not distributed in the VPK, yet the textures are present.

Contributors to items released in any event crate (such as the Nice Winter Crate, Scorched Crate, Fall Crate, etc) received Self-Made quality versions of those Crate Keys. These are then usually converted into Self-Made Mann Co. Supply Crate Keys at the same time as all other keys of that event.

Keys are internally called decoder rings in the game code.

Unused content

Instead of the Gun Mettle Key, the Gun Mettle cases originally had their own separate keys, not unlike the Naughty and Nice crates.